Jim,

I suspect much of the color we see (with eyeballs) is from the feathers'
diffraction-grating effect rather than pigment. May be that when the main
light source is from camera, rather than from side, you get a different part
of the spectrum. Anyhow, it's a hypothesis.

Al Wagar
Shoreline

On 12/22/08 2:07 PM, "Jim Greaves" <lbviman at blackfoot.net> wrote:

> Regarding yellow Anna's -- I notice when using flash on Anna's that
> the back gets a yellow hue to it -- sometimes so much so that it
> overtakes the greens, and I think I've set the camera wrong! There
> must be some subtle shades in the feathers (much like reds and
> yellows overlapping?) that we do not readily see until we've somehow
> captured it -- do you use flash? -- Jim Greaves, Thompson Falls MT
>
>